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  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
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<body>
  <script>

    // 函数表达式
    // let b = function () {
    //   console.log('666')
    // }

    // b()

    // 立即执行函数
    (function () {
      console.log('6656')
    })();

    (function () {
      console.log('6666666')
    })();

  </script>
</body>

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